Adjunctive therapies to non-surgical periodontal treatment have significant advantages in susceptible patients as it helps to modulate the host immune response. In this study, we compare the effectiveness of oxygen releasing gel (BM) alone, or associated with photodynamic therapy (PDT), after scaling and root planning (SRP), as adjuvants in the treatment of ligature-induced experimental periodontitis (EP) in rats. Our findings indicate that treatment with BM, PDT, and BM+PDT groups at both 7 and 30 days resulted in decreased alveolar bone destruction in the furcation area of mandibular molars compared to the EP and SRP groups. At 30 days, the PDT and BM+PDT groups enhanced the resolution of inflammation by decreasing the inflammatory infiltrate and increasing alveolar bone neoformation. Treatment with BM gel alone also improves the repair of periodontal tissues but is less effective compared to PDT. Finally, combining BM with PDT appears to diminish the effects of PDT.